THIRD ANNUAL YEAR BOOK — PART IX. 557 



engine to heat the feed water for boiler. Here we found the cylinder oil 

 transmitted to the milk from the boiler, thus giving a decided oily flavor 

 to the butter. The use of boiler compounds showed their injurious effects 

 also. Why live steam should be used for heating milk at the present time 

 is a mystery to me. Many of the live steam heaters not only injure the 

 flavor by transmitting impurities from the boiler but the heating is not 

 sufficient to give the best, or the desired results. The heating of milk is 

 supposed to help the fluidity of the fat globules. The quick, flashy heat- 

 ing of milk has very little effect on the fat globules, therefore the separa- 

 tion is not as perfect. Milk should be heated for some time before separa- 

 tion to get the best results. The centrifugal separation of milk is a won- 

 derful process. Think of a separator bowl making from six to twenty thou- 

 sand revolutions per minute. Here we see sweet milk put into the machine 

 and skim milk and cream immediately separated. Most any separator 

 will skim clean to a certain limit if the machine is run perfectly smooth 

 and at the proper speed. A little vibration of the machine causes a remix- 

 ing of the cream and no separator will skim thoroughly clean that vibrates. 

 This is where some makers in large creameries lose possibly more than 

 their wages. The next thing is cream ripening which is possibly the most 

 important step in the whole process as this fs a factor that largely controls 

 the flavor, and flavor is the quality that distinguishes butter from lard, 

 tallow or any of the other fats. Flavor does not come by chance. Every 

 intelligent butter maker is fully aware of the uncertainty and difficulty 

 of producing a uniform high flavor. Experience has taught us that when 

 certain processes are followed, the resulting product is usually of at least 

 fair quality. But even under the best sanitary conditions the product is 

 often strikingly variable in flavor from day to day. The cause of these var- 

 iations and difficulties open up an important field for future investigation. 

 The subject is of great scientific interest as well as of practical value. But- 

 ter fat in itself is supposed to have little or no flavor. It was for- 

 merly supposed that the flavor was largely due to the volatile fatty acids. 

 The flavor substances are possibly absorbed by the fat or are associated 

 with the other constituents which compose a portion of the butter. The 

 chemical nature of the substance which give the delicate flavor and aroma 

 are not known. I think I am safe in saying that it is generally accepted 

 now that the flavor substance whatever they may be are the products result- 

 ing from the breaking down of the milk solids. It was shown by Professor 

 Storch that they are the result of the growth of bacteria. Professor Storch 

 tells that the flavor of good butter comes from the decomposition of milk 

 sugar. I might say that Dr. Weigmann, the noted German bacteriologist, 

 held the same view when I visited his labaratory a little over a year ago. 

 Dr. Conn, on the other hand, thinks that the nitrogenous material in milk % 

 as the casein and albumen, furnish the product which gives the flavor. 

 The feed consumed by the animal no doubt has an influence on the flavor 

 as well as on the color and the hardness of the butter. But in general this 

 influence is much less than the effect of fermentation which has taken 

 place in the milk and cream. In cases where feeds, such as turnips or wild 

 onions and weeds are consumed by the cows, the flavor will undoubtedly 



